艾萨法炼铜过程中砷元素的迁移特性及控制方法

Migration characteristics and control methods of arsenic in copper smelting by ISA process

高砷铜精矿火法熔炼时,砷及其化合物大部分挥发进入气相(烟气),存在公辅设备运行成本高、环境污染严重等一系列的问题。本文以艾萨炉-PS转炉-阳极炉强化铜冶炼生产工艺为例,研究了杂质元素砷在艾萨炉熔炼、贫化电炉还原、转炉吹炼和反射炉精炼的存在状态和迁移特性,其中58.8%进入艾萨电尘,另有0.4%会遗留在阳极铜中。本试验应用氧化挥发法和加碱造渣法,提出了熔炼工序、吹炼工序、精炼工序3个工序的控制措施。针对砷易挥发、难固化的特点,采用喷吹罐鼓入碱性脱杂剂和加装艾萨炉导料管等控制方法,能提升火法阶段的固砷效果和除砷量,解决了冶炼含砷烟尘量大以及铜产品砷含量过高的问题。

When high arsenic copper concentrate is subjected to pyrometallurgy, arsenic and its compounds mostly volatilize into gas phase(offgas), which leads to a series of problems such as high operation cost of equipment and serious environmental pollution. This paper took the ISA furnace-PS converter-anode furnace intensive copper smelting process as an example, studied the state and migration characteristics of impurity arsenic in ISA furnace smelting, cleaning furnace reduction, converter converting and reverberatory furnace refining, of which 58.8% of arsenic entered ISA furnace dust and 0.4% remained in anode copper. In this test, oxidation volatilization method and alkali addition slagging method were applied, and the control measures of three procedures, namely smelting, converting and refining, were put forward. According to the arsenic characteristics of easy volatility and difficult solidification, the control methods such as injecting alkaline impurity remover and installing ISA furnace guide pipe can improve the arsenic solidification effect and arsenic removal amount in pyrometallurgical stage, and solve the problems of large amount of arsenic-containing dust in smelting and high arsenic content in copper products.